Figure 3

Microscopic bronchial reconstruction. (A) Small bronchi were dilated with mild infiltration of small round inflammatory cells and their epitheliums were replaced by goblet cell hyperplasia. (Scale bar = 500 μm) (Elastic van Gieson stain). (B) The prominent concentric fibrosis with mild infiltration of small round inflammatory cells was present in the submucosal layers, resulting in membranous bronchiolar luminal narrowing and complete occlusion. (Scale bar = 500 μm) (Elastic van Gieson stain). (C) The marked proliferation of elastic fibers, lack of inflammatory cells infiltration was observed in the more distal than membranous bronchioli. (Scale bar = 200 μm) (Elastic van Gieson stain).